1. Field of the Invention
The present invention relates to an improved coke oven battery and to an improved method for production of coke and byproducts and more particularly to an improved processing of the filling gas.
2. Brief Description of the Background of the Invention Including Prior Art
All modern by-product coke ovens are constructed to take a definite volume of coal per charge and are charged from a larry car operating between overhead coal storage bins and the ovens. Improvements in larry cars have been directed toward making possible better charging practices. The aims of such improvements are for example to reduce charging time, to reduce the number of passes of the leveling bar necessary for leveling and to make a smokeless charge. Nevertheless there are still produced considerable amounts of filling gas during charging and filling operation of the ovens. It is known that the treatment of the filling gas escaping during the charging and filling procedure from the oven chambers provides a serious problem in view of the more severe regulations relating to environmental protection. The problem is further increased by a modern and increasing trend to charge and fill the oven chambers with preheated coal instead of the normal that is wet coal. However, the filling gas volume and the dust contents of the filling gas are thereby not inconsiderably increased. There has been no lack of proposals in the past for handling the problem of the filling gas sucking off and of its treatment. In pursuing this goal it has been proposed for example to burn the filling gas directly at an installation on the larry car for burning the filling gas. This method however encounters increasing difficulties for reasons of environmental protection and for plant safety reasons. It has also been proposed to withdraw the filling gas separately from the production gas, that is the raw coke oven gas, via a separate filling gas conduit and after performing a corresponding dedusting and tar removal to feel the filling gas either back into the oven or to add the filling gas to the raw coke oven gas.
The filling gas can be purified by a dry method employing cyclone precipitators and/or electrofilters or by a wet method employing washers. It is clear that separate provisions and apparatus for the purification of the filling gas cause additional capital and operating costs for the coke battery. In case washers are employed for this purpose in addition the run off washing liquid containing the dust and tar constituents of the filling gas has to be purified in a separator such as a decanter before the washing liquid can be employed again for treating the filling gas in the washer.